Knife for cloth-cutting machines or the like



FSL; 2 1926. 1,571,441

G. E.' ULRICH KNIFE FOR CLOTH CUTTING MACHINES 0R THE LIKE Filed May 28, 1924 A TTONEY.

Patented Feb. 2, 1926.

UNITED STATESA Latin PATENT OFFICE.

GEORGE E. ULRICH, OF BUFFALO, NEW YORK, ASSIGNOR TO EASTMAN MACHINE COMPANY, 0F BUFFALO, NEW YORK.

KNIFE FOR CLOTH-CUTTING MACHINES OR THE LIKE.

Application filed 'May 28, 1924. Serial No. '6,367.

elongated knife or blade is provided which is secured at one end to a slide or other means for imparting reciprocating motion thereto.- The knife is arranged to reciprocate or slide in a substantially upright guide slot formed in a standard or leg, on the upper end of which a motor and the neces sary driving connections are mounted, while the lower end of the standard is secured to a. throat plate attached to the usual base plate which moves beneath the cloth or other material being cut. The throat plate is provided with the usual longitudinal throat or opening extending therethrough and which forms substantially a continuation or enlargement of the guide slot, and the knife moves towards and from the throat when cutting they material.

Heretcfore, in machines of this type, the

knife has been formed with a straight, continuous square or flat heel portion or back edge, and the opposite sides of the knife ex-' tend parallel or substantially parallel to each other, and the guide slot is of similar shape and lits closely vagainst the back of the knife and a portion. of each side, so as to leave the cutting edge exposed or extending out of the guide slot. The back of the knife therefore engages with the back of the guide slot for the full length of the' knife, in its movements up and down therein.

Inpractice, this formation ofthe knife and resulting continuous contact with the back of the guide slot, is objectionable for the reason that small particles of lint or the like, from the material being cut, enter the lower end of the guide slot from the throat and from the space above and adjacent thereto during the upward strokes of the knife, with the result that the lint and the lubricant supplied to the knife in the slot form a gummy deposit which clogs the guide slot and impedes the free action of the knife to such an extent that the proper working of the machine is impossible without frequent cleaning of the knife and The principal object of the present invention is to provide a cutting knife or blade for reciprocating cloth cutting machines which is formed and adapted, in its recipro eating movements, to keep the slot free of accumulations or deposits and thereby overcome the difficulties heretofore encountered.

Another object is to improve the construe# tion of cloth cutting knives in the other respects hereinafter specified and claimed.

In the accompanying drawings;

Fig. 1 is a fragmentary side elevation of cloth cutting machine of therreciprocating type, provided with a cutting knife embodyingthe invention.

Figi 2 is a longitudinal sectional elevation, on an enlarged scale,` of the standard and throat plate of the machine, showing the knife in the guide slot in said standard.

Fig. 3 is an elevation of a side face of the improved knife;

i Fig. 4 is a horizontal sect-ionl on line 4 4, Fig. 2. l

Fig. 5 is a horizontal section of the knife .on line 5-5, Fig. 3.

Y 11 is provided with a throat or longitudinal recess 13 extending therethrough to the bottom of the base plate, 'and having a reduced narrow opening '13a at the top, and the standard 10 is formed with a knife guiding slot 14 extending from the top of the standard to the bottom and ending in the opening 13)a of the throat 13. A motor 15 is fixed to a lateral Varm 16 of the standard, said motor being adapted to actuate suitable reciprocating mechanism, including the crank or pitman 17, which is pivotally secured to a slide 18 movable in a vertical guide 19, said slide 18 being rigidly secured to the bifurcated upper end 20 of the cuttingknife A. by bolts or the like, 21, Whereby "the necessary vertical reciprocating movements are imparted to the kknife A.

The knife guide slot 14 is formed with 5 parallel side walls 24 and a rear or back Wall so asto extend'substantially the full length of theknife and this edge contacted With tlie back,,25 ofthe guide slot throughout the full f length of the knife.

In the present invention the knife vis formed so as to. remain out .ofcontact with the backof the guide slot for the greater portionof the length of the knife, so 'as to form.

a spacebetiveen theseparts into Which the accumulations of lint and oil may pass to prevent, or reduce to a minimum, the clogging1 ofthe, guide slot and consequent interference With the free action of the knife. This ispreferablyr accomplished, as shown inthe; dra-Wings, bycutting away a portion ofthe .back edge 27'of-the knife A', as at .27, so as to leavevonly arelatively short portion of this edge 27, preferably at the. bottom, tol contact ,with the back Wall-25 of the guide slot 14, and providing a 'free' space or channel 29 inthe guide slot 11i-.behind the knife for the remainder of the length thereof.

Incutting away the :back edge of the knifeas explained, a shoulder 30. is' left be tW'een-.theedges 27, k27'? and this shoulder is preferably madef-,abruptror square, and in,

the reciprocating movements of the knife A in; theknifeguide'slot14', to and from the throat opening 13a, the lint and other.accu`m.

ulationsfiasthey.: .workinto .andpass' upwardly from the loWerj end of the slot, Will=- pass into the; channel- ,.29; behind the knifef; wherethey Willbe engaged/Eby. kthe shoulder Y 30 infthe upwardzmovements of said knife and will ybe gradually pu-slredupwardlv andy ejected at the upper endroftheguidefslot. rlhesquareV or abrupt shoulder 30 acts as a scraperto keep-the backend side: Walls .cffthelcha-nnel freeof accumulations. and

makes-the knifepracticallyl self cleaning.

The described formation of the cutting.

knife A issuch thatithe yefiiciencyof recipro; eating cloth cutting machines provided `with the knife is:.greatlvincreased and ,themachine Will-.Operate With-'out `cloivzging of` the;-

kuifeinthe guide.slot,-1"and,v by preventing the deposits from accumulating, .redufcesthe friction and lconsequent.- heating to. which such; tknives have heretofore been subjected.

Further, the .improved `knifecan bepro-i duced Without anyincrease in the cost of manufacture.

'I claim as my invention:

1. In a. cloth cutting machine of the character described, a standard having a knife guiding slot therein, and a reciprocable cutting knife the rear portion of which is shaped to remove the lint and other accumulations from all parts of said guide slot. e 2. A clothx cutting machine of the character described, including a standard having a knife guiding slot with parallel side Walls and a straight backv Wall connecting said side Walls, and a reciprocable cutting knife having side faces engaging said side Walls, and aback edge formed with a relatively short portion adaptedvto engage said hack wall of the slot` said portionbeing shorter than the cutting edge of saidknife, and a relatively longer portion which remains out of Contact therewithfto .provide a Achannel into which lintand other accumulations may pass toprevent the clogging of said knife. in said slot, said knife having a part extending into said channel and adapted to ejectsaid accumulations from said guiding slot.

. 3. In a cloth cutting machinev of the character described including a standard having.

a knife guiding kslot formed Withparallel side ivallsjand a straight. back Wall connectingsaid side Walls, and a reciprocable cutting knifehaving side faces engaging said sidewalls. and a back edge formed with av bination of a knife guiding slot` formed iwithsidetwalls and ay back'wall, and av reciprocable cutting knife having side faces engaging said side Walls and a back edge, said back edge of said knife contacting ivith a portion only ofsaid .back `walhsaid portion being shorter than the cuttingedgeof' said knife,4 andthe portions ofsaid back Wall which; areinot in contact with `theback edgeof saidknife serving to receive lint and other accumulations Without vbinding said knife jin said slot.

- GEORGE E. ULRICH. 

